I think the answer is to be found in the history of the EFI touring bikes. When they first came out with the Marelli injection and the EFI bikes cost significantly more then an otherwise equal carb bike and the EFI bikes could be considered the flagships, at least from the factories point of view, it just wouldn't do for them to be outperformed.
So, they gave the EFI bikes lower gearing and better cams. They still were outperformed but the issue was confused enough for plausible deniability at least with the general public.
Fast forward to 02, just before the Delphi touring bikes came out there was a lot of conflicting information from the factory regarding the gear ratios. They must have played with the idea to use the same ratio on both bikes.
While in totally stock form the Delphi bikes slightly outperform the carb bikes overall, even a totally stock carb bike will pull better from very low rpm. The Delphi bikes definitely hate low rpm, so they probably figured they may be better off leaving the lower gear ratio in for the EFI bikes.
It really is a strictly academic issue, there is no reason whatsoever why they shouldn't run all day long at 4000 or even 4500 rpm.